Printing apparatuses which print information such as a desired character or image on a printing medium such as paper are widely used as an information output apparatus for a personal computer, facsimile apparatus, and the like. These printing apparatuses are used as printers in modern business offices, in other business affairs departments, and for personal use. The printing apparatuses have been developed and improved for achieving further cost reduction and higher resolution while strongly requiring not only higher resolution but also higher-speed printing.
Of these printing apparatuses, an inkjet printing apparatus which prints by discharging ink from orifices arranged on printing elements utilized for quiet non-impact printing can attain high resolution and high-speed printing due to its structural feature, and is widely spread as a low-cost color printer or the like. The inkjet printing apparatus prints by discharging ink in accordance with desired printing information by using a printhead having a printing element with an orifice and an electrothermal transducer which generates discharge energy for discharging ink from the orifice.
It is conventionally known that the inkjet printhead has an arrangement in which a plurality of printing elements are aligned in one or a plurality of arrays. As an arrangement using such an inkjet printhead, a plurality of inkjet printheads are mounted on a carriage in accordance with the types of ink, or a plurality of ink cartridges are mounted on a single inkjet printhead. An inkjet printhead and ink cartridge are integrated in the former arrangement, and are separable in the latter arrangement.
As the resolution and image quality have been required in recent printing, the performance of the inkjet printhead has greatly improved. In particular, the throughput has increased by increasing the number of integrated printing elements or the number of concurrently drivable printing elements.
Along with this, the function of the ink cartridge has also been advanced. Ink itself is required to have a carefully prepared component and composition ratio in order to satisfy printing performance. For example, a pigment has replaced a dye which has conventionally been adopted as a coloring material, in order to enhance weather resistance. Inks of respective colors react with each other in multicolor printing, and a resin component for promoting fixing is added for high-speed printing.
When ink whose component and composition ratio change with the improvement of printing performance is employed, the printing apparatus functions without any problem and ink performance can be fully exerted as far as ink is simply used in the printing apparatus. However, when a plurality of types of inks are mixedly used, for example, different types of inks are alternately used in the same printing apparatus, the different types of inks mix with each other, and ink may coagulate within the printhead or adhere to the ink discharge surface of the printhead.
In some cases, in order to prevent mixing of different types of inks in the same printhead, an ink cartridge incompatible in shape with other ink cartridges must be newly prepared.
However, if ink cartridges (ink tanks) incompatible in shape are introduced to many printer models, ink cartridges of new shapes appear on the market as new printers are released one after another. As a result, the customer is confused in selecting the type of ink cartridge suitable to his printer, or a suitable ink cartridge may not be available to the customer due to an insufficient space of the stockroom of the shop when he needs it.
As an approach which solves this problem, there have been proposed an inkjet printing apparatus and ink cartridge, which incorporates a memory element which stores pieces of information such as the type of ink and remaining ink amount in the ink cartridge and the expiry date. A printing apparatus main body to which the ink cartridge is mounted detects these pieces of information from the memory element, and starts operation. For example, Japanese Patent Laid-Open No. 3-67657 discloses an arrangement in which a medium that stores information on driving of an inkjet head is arranged on an ink cartridge that contains ink so as to drive the printhead under driving conditions complying with the ink composition.
Pieces of information on ink make it possible to use under optimal conditions an inkjet printing apparatus to which an ink cartridge is mounted, an inkjet printhead which actually discharges ink, and ink contained in the ink cartridge, and are stored in the memory element of the ink cartridge.
As an arrangement which controls a printing apparatus main body in correspondence with a mounted printhead, for example, Japanese Patent Laid-Open No. 5-8383 discloses an arrangement in which the type of mounted printhead is detected and printing control corresponding to the type of printhead is performed.
There has also conventionally been known an arrangement in which printhead information is read from a memory means arranged in the printhead and the printing apparatus main body is controlled on the basis of characteristic information such as the discharge amount (e.g., Japanese Patent Laid-Open No. 2001-63058).
In the conventional inkjet printing apparatuses, an exchangeable inkjet printhead and ink cartridge are convenient, but at the same time may cause various system errors.
Most of the causes of such errors result from the difference in ink composition. This may physically degrade the functions of not only the ink cartridge but also the inkjet printhead and inkjet printing apparatus. Of various system errors, clogging of the inkjet printhead is especially fatal. This is because clogging is directly linked with a printing failure and degradation of the printing quality, and exchange of a purchased inkjet printhead due to clogging impairs customer's reliability of the product. Hence, demands arise for a product which can avoid any error in advance in order to provide a high-reliability inkjet printing apparatus even if clogging is caused by the customer who intentionally or unintentionally mixedly uses ink cartridges different in ink composition.